schema: Log debug instead of warning when jsonschema is not available.

When operating in expected path, cloud-init should avoid logging with
warning. That causes 'WARNING' messages in /var/log/cloud-init.log.
By default, warnings also go to the console.

Since jsonschema is a optional dependency, and not present on xenial
and zesty, cloud-init should not warn there.

Also here:
* Add a test to integration tests to assert that there are no
  warnings in /var/log/cloud-init.log.
* Update one integration test that did show warning and the related
  documentation and examples.

LP: #1724354

8 files changed, 32 insertions, 9 deletions

diff --git a/cloudinit/config/cc_users_groups.py b/cloudinit/config/cc_users_groups.py
index b80d1d36..f363000d 100644
--- a/cloudinit/config/cc_users_groups.py
+++ b/cloudinit/config/cc_users_groups.py
@@ -15,7 +15,8 @@ options, see the ``Including users and groups`` config example.
 Groups to add to the system can be specified as a list under the ``groups``
 key. Each entry in the list should either contain a the group name as a string,
 or a dictionary with the group name as the key and a list of users who should
-be members of the group as the value.
+be members of the group as the value. **Note**: Groups are added before users,
+so any users in a group list must already exist on the system.
 
 The ``users`` config key takes a list of users to configure. The first entry in
 this list is used as the default user for the system. To preserve the standard
diff --git a/cloudinit/config/schema.py b/cloudinit/config/schema.py
index bb291ff8..ca7d0d5b 100644
--- a/cloudinit/config/schema.py
+++ b/cloudinit/config/schema.py
@@ -74,7 +74,7 @@ def validate_cloudconfig_schema(config, schema, strict=False):
     try:
         from jsonschema import Draft4Validator, FormatChecker
     except ImportError:
-        logging.warning(
+        logging.debug(
             'Ignoring schema validation. python-jsonschema is not present')
         return
     validator = Draft4Validator(schema, format_checker=FormatChecker())
diff --git a/doc/examples/cloud-config-user-groups.txt b/doc/examples/cloud-config-user-groups.txt
index 9c5202f5..0554d1f7 100644
--- a/doc/examples/cloud-config-user-groups.txt
+++ b/doc/examples/cloud-config-user-groups.txt
@@ -1,8 +1,8 @@
 # Add groups to the system
-# The following example adds the ubuntu group with members foo and bar and
-# the group cloud-users.
+# The following example adds the ubuntu group with members 'root' and 'sys'
+# and the empty group cloud-users.
 groups:
-  - ubuntu: [foo,bar]
+  - ubuntu: [root,sys]
   - cloud-users
 
 # Add users to the system. Users are added after groups are added.
diff --git a/tests/cloud_tests/testcases/base.py b/tests/cloud_tests/testcases/base.py
index bb545ab9..b2b5b4b1 100644
--- a/tests/cloud_tests/testcases/base.py
+++ b/tests/cloud_tests/testcases/base.py
@@ -72,6 +72,10 @@ class CloudTestCase(unittest.TestCase):
         result = self.get_status_data(self.get_data_file('result.json'))
         self.assertEqual(len(result['errors']), 0)
 
+    def test_no_warnings_in_log(self):
+        """Warnings should not be found in the log."""
+        self.assertNotIn("WARN", self.get_data_file('cloud-init.log'))
+
 
 class PasswordListTest(CloudTestCase):
     """Base password test case class."""
diff --git a/tests/cloud_tests/testcases/examples/including_user_groups.py b/tests/cloud_tests/testcases/examples/including_user_groups.py
index 67af527b..93b7a82d 100644
--- a/tests/cloud_tests/testcases/examples/including_user_groups.py
+++ b/tests/cloud_tests/testcases/examples/including_user_groups.py
@@ -40,4 +40,10 @@ class TestUserGroups(base.CloudTestCase):
         out = self.get_data_file('user_cloudy')
         self.assertRegex(out, r'cloudy:x:[0-9]{3,4}:')
 
+    def test_user_root_in_secret(self):
+        """Test root user is in 'secret' group."""
+        user, _, groups = self.get_data_file('root_groups').partition(":")
+        self.assertIn("secret", groups.split(),
+                      msg="User root is not in group 'secret'")
+
 # vi: ts=4 expandtab
diff --git a/tests/cloud_tests/testcases/examples/including_user_groups.yaml b/tests/cloud_tests/testcases/examples/including_user_groups.yaml
index 0aa7ad21..469d03c3 100644
--- a/tests/cloud_tests/testcases/examples/including_user_groups.yaml
+++ b/tests/cloud_tests/testcases/examples/including_user_groups.yaml
@@ -8,7 +8,7 @@ cloud_config: |
   #cloud-config
   # Add groups to the system
   groups:
-    - secret: [foobar,barfoo]
+    - secret: [root]
     - cloud-users
 
   # Add users to the system. Users are added after groups are added.
@@ -24,7 +24,7 @@ cloud_config: |
     - name: barfoo
       gecos: Bar B. Foo
       sudo: ALL=(ALL) NOPASSWD:ALL
-      groups: cloud-users
+      groups: [cloud-users, secret]
       lock_passwd: true
     - name: cloudy
       gecos: Magic Cloud App Daemon User
@@ -49,5 +49,8 @@ collect_scripts:
   user_cloudy: |
     #!/bin/bash
     getent passwd cloudy
+  root_groups: |
+    #!/bin/bash
+    groups root
 
 # vi: ts=4 expandtab
diff --git a/tests/cloud_tests/testcases/modules/user_groups.py b/tests/cloud_tests/testcases/modules/user_groups.py
index 67af527b..93b7a82d 100644
--- a/tests/cloud_tests/testcases/modules/user_groups.py
+++ b/tests/cloud_tests/testcases/modules/user_groups.py
@@ -40,4 +40,10 @@ class TestUserGroups(base.CloudTestCase):
         out = self.get_data_file('user_cloudy')
         self.assertRegex(out, r'cloudy:x:[0-9]{3,4}:')
 
+    def test_user_root_in_secret(self):
+        """Test root user is in 'secret' group."""
+        user, _, groups = self.get_data_file('root_groups').partition(":")
+        self.assertIn("secret", groups.split(),
+                      msg="User root is not in group 'secret'")
+
 # vi: ts=4 expandtab
diff --git a/tests/cloud_tests/testcases/modules/user_groups.yaml b/tests/cloud_tests/testcases/modules/user_groups.yaml
index 71cc9da3..22b5d706 100644
--- a/tests/cloud_tests/testcases/modules/user_groups.yaml
+++ b/tests/cloud_tests/testcases/modules/user_groups.yaml
@@ -7,7 +7,7 @@ cloud_config: |
   #cloud-config
   # Add groups to the system
   groups:
-    - secret: [foobar,barfoo]
+    - secret: [root]
     - cloud-users
 
   # Add users to the system. Users are added after groups are added.
@@ -23,7 +23,7 @@ cloud_config: |
     - name: barfoo
       gecos: Bar B. Foo
       sudo: ALL=(ALL) NOPASSWD:ALL
-      groups: cloud-users
+      groups: [cloud-users, secret]
       lock_passwd: true
     - name: cloudy
       gecos: Magic Cloud App Daemon User
@@ -48,5 +48,8 @@ collect_scripts:
   user_cloudy: |
     #!/bin/bash
     getent passwd cloudy
+  root_groups: |
+    #!/bin/bash
+    groups root
 
 # vi: ts=4 expandtab